| 摘要 |
PURPOSE:To enable automatic setting of a reference value for checking and make the checking effective by providing a signal processing circuit to switch check mode and learning mode. CONSTITUTION:A signal processing circuit 10 switches a learning mode by which a reference value for deciding the qualification of printing and tolerance can be set, and a mode by which checking is performed according to an already established reference. The check mode enables comparison of the calculated position of each color mark with an established reference value to calculate an error. Then if this error falls within a tolerable range, printing is decided as 'qualified', and if the error remains outside the range, printing is decided as 'unqualified'. Accordingly, a marker paper is inserted and an alarm output as procedures to deal with such defects. The learning mode prepares plural pieces of printed matter decided as 'qualified' by visual check beforehand, calculates the position of color mark on each printed matter, and seeks a mean value of these data as a reference value. A tolerable error is preset to meet the ranking of printing precision, and a tolerable error to the mean value is automatically set. |
